Configuring the MVI56E-MCMR Module MVI56E-MCMR ♦ ControlLogix Platform
User Manual Modbus Communication Module with Reduced Data Block
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Read Input Status 1x (Modbus Function Code 2)
Use this command to read Input Coils from a slave device. These are single bit
addresses within a Modbus slave device. Unlike Coils 0x, the Input Coils are
Read Only values and cannot be written to by a Modbus Master device. Also like
the Coils 0x, the Internal Address field of this command is defined down to the bit
level within the module memory.
The following illustration shows a sample command to read Modbus addresses
10081 to 10090 of Modbus Slave Device Address 1.
The module will send the command every time it goes through the
command list.
Places the data read from the slave device into the module at
address 16480. Internal Address 16480 of the module memory will be
copied into the tag MCMR.DATA.READDATA[30] (bit16480 / 16 =
register 1030).
Reads 16 consecutive registers from the slave device.
Issues the Modbus command to Modbus Slave Device Address 1.
Issues Modbus Function Code 2 to Read Input Coils.
MB Address in Device = 80
Function Code 2, MB Address in Device of 80 will read address
10081
Along with a count of 16, this command reads 10081 to 10096.